1. Field of the Invention
This invention relates to a conduit for supporting electrical wiring between a vehicle body and a side door of a motor vehicle, utilizing a hinge mechanism having a quadric crank chain.
2. Description of the Prior Art
In most cases, the side door in a motor vehicle, such as a passenger car, is installed in a manner to be rotatable about a hinge affixed to a vehicle body for opening or closing. In order to allow an occupant of the motor vehicle to open or close the side door for getting in or out of the motor vehicle, a door opening angle corresponding to the total length of the side door is required. With this construction, when a space at the side of the motor vehicle is small, there are many instances where it is difficult for the occupant to get on or off the vehicle because the side door cannot be opened sufficiently.
In contrast a side door hinge mechanism in a motor vehicle may include a quadric crank chain. Such a mechanism comprises a front rotary link interconnecting two points which are disposed at the forward portions of a vehicle body and a side door constituting two rotary centers out of four pivotal points. The four pivotal points include two points disposed on the vehicle body and spaced apart from each other in the longitudinal direction of the vehicle body and two points disposed on the side door and spaced apart from each other in the longitudinal direction of the side door. A rotary link interconnecting two points disposed at the rear sides as rotary centers, a portion between the two points on the vehicle body, and a portion between the two points on the side door.
With the side door hinge mechanism utilizing the above-described quadric crank chain, a required space at the side of the door can be reduced while a desired space around feet of the occupant is secured. As a consequence, even when the space at the side of the door is small, the occupant can open or close the side door to get in or out of the vehicle.
Now, in general, in the side door of a motor vehicle, there may be provided a power window regulator, a device for controlling the power window regulator, an electromagnetic lock device and a switch for operating the lock device. In this case the side door and a vehicle body are electrically connected to each other through a wire harness.
When the side door utilizing the quadric crank chain and the vehicle body are connected to each other by use of the wire harness, the inner end portion of the side door, which differs from the side door having an ordinary hinge mechanism, is greatly separated from the vehicle body during the opening of the door. This construction makes it is difficult to provide a route for the wire harness.
Furthermore, when the vehicle body and the side door are connected through the wire harness, the working stroke of the side door during the opening or closing is larger than that of the side door having the conventional hinge mechanism as described above, so that it becomes difficult to house the wire harness during the closing of the door.
Further, the wire harness should be installed with at least a portion thereof being exposed in a compartment to facilitate the workability of installation. However when the wire portion is exposed, there is presented a problem that the exposed portion should be rigged in order to match with the coloring of the interior of the compartment, and the like.
In contrast thereto, to absorb the great opening and closing strokes of the side door by the wire harness, there may be proposed to use electric wire and molded parts, which are of special shapes. In this case, such disadvantages are presented that the cost is increased and installation becomes more difficult.
Furthermore, to obviate the above-described disadvantage, opposing electric contact points may be used, which are brought into contact with each other when the side door is closed. These contact points are provided on the side door and the vehicle body and no wire harness is used. In this case, such problems are presented that it is difficult of compose circuits of a multiplicity of types and the cost is increased.
Furthermore, in the side door having the hinge mechanism utilizing the above-described quadric crank chain, at least one of the rotary links interconnecting the vehicle body and the side door is exposed in the compartment.
As a consequence, in this case, the side surface of the rotary link exposed in the compartment should be covered by an interior trim material, however, the color and material quality of interior trim material are varied depending upon the coloring of the interior of the compartment, grade and the like. The installation of the interior trim material on the rotary link also should be easy as viewed from the workability of installation.